Slide 1

Pregnancy Questioning Audit: by Fathima Hasan Mohamed,Senior Radiographer.

Introduction

The imaging of pregnant women presents a unique challenge to radiologists because of the concern about the radiation risk to the conceptus (ie, embryo or fetus).Thousands of pregnant women are exposed to ionising radiation each yearLack of knowledge is responsible for great anxiety and probably unnecessary termination of pregnanciesFor most patients, radiation exposure is medically appropriate and the radiation risk to the fetus is minimal.

Lack of knowledge is responsible for great anxiety and probably unnecessary termination of pregnanciesFor most patients, radiation exposure is medically appropriate and the radiation risk to the fetus is minimal

Example: justified use of CT Pregnant female, was in motor vehicle accident

Fetal skull

ribs

Blood outside uterus

Fetal dose 20 mGy

AAH POLICY- EMERGENCY

INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION

During emergency, if informed consent cannot be obtained or no relative is available to sign on behalf of the patient, the physician shall clearly document in electronic radiology requisition, the reason for the examination and sign the consent. The radiologist will document the reason for the examination and steps taken to minimize risks to the embryo/fetus in the radiology report.

INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION

3 minute CT exam and taken to the operating room. She and the child survived

Free bloodKidney tornoff aorta (no contrast in it)Splenic laceration

Fetal radiation riskThere are radiation-related risks throughout pregnancy that are related to the stage of pregnancy and absorbed doseRadiation risks are most significant during organogenesis and in the early fetal period, somewhat less in the 2nd trimester, and least in the 3rd trimester

LessLeastMost risk

INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION

Radiation-induced malformationsMalformations have a threshold of 100-200 mGy or higher and are typically associated with central nervous system problemsFetal doses of 100 mGy are not reached even with 3 pelvic CT scans or 20 conventional diagnostic x-ray examinationsThese levels can be reached with fluoroscopically guided interventional procedures of the pelvis and with radiotherapy

INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION

Central nervous system effects

During 8-25 weeks post-conception the CNS is particularly sensitive to radiationFetal doses in excess of 100 mGy can result in some reduction of IQ (intelligence quotient)Fetal doses in the range of 1000 mGy can result in severe mental retardation and microcephaly, particularly during 8-15 weeks and to a lesser extent at 16-25 weeks

Radiation RiskRadiation exposure that is extra-abdominal will not contribute significant radiation dose to the developing embryo/fetus.For most extra-abdominal exams, including CT, the radiation dose to the embryo/fetus is less than 0.1 mSv (10 mrem).

Radiation RiskRadiation exposure that is extra-abdominal will not contribute significant radiation dose to the developing embryo/fetus.For most extra-abdominal exams, including CT, the radiation dose to the embryo/fetus is less than 0.1 mSv (10 mrem).

The risk of malformation is increased only at levels above 150 mSv (15 rem).

Radiation RiskIf the radiation dose is received between the second and eighth post-conception weeks, therapeutic abortion based solely on radiation exposure is not advised for doses less than 150 mSv (15 rem).

Approximate fetal doses from conventional x-ray examinationsData from the UK, 1998DoseExaminationMean (mGy)Maximum (mGy)Abdomen 1.4 4.2Chest